Biliary atresia and idiopathic neonatal hepatitis are the most common causes of jaundice and hyperbilirubinemia, which extends beyond the newborn period. The long-term goal of the Biliary Atresia Research Clinical Research Consortium (BACRC) is to establish a database of clinical information and serum and tissue samples from children with biliary atresia (BA) and idiopathic neonatal hepatitis (INH) to facilitate and perform clinical, epidemiological and therapeutic research in these two important pediatric liver diseases. This application to be the DCC brings together experienced investigators from biostatistics, pediatric surgery, pediatric hepatology and transplantation. The DCC will: 1. Establish longitudinal cohort database for patients with BA and INH 2. Provide expertise in the design, conduct, and analysis of multicenter trials 3. Coordinate the implementation of the study protocols approved by the steering committee, including centralized database management with either centralized or remote data entry 4. Monitor sites with respect to data quality 5. Develop the plan for the data analysis, perform the analysis and collaborate on the preparation to the publications that will result from these studies6. Establish and maintain a Specimen Core Facility to serve as a central repository for the BACRC. 7. In our application we propose the construction of a longitudinal cohort database and detail how such information would be used to analyze the natural history of patients with biliary atresia who undergo a Kasai procedure. We also propose a multicenter prospective randomized clinical trail of steroid therapy after the Kasai procedure to highlight the role of the DCC in this mission. It is recognized the steering committee will develop and approve all protocols to be implemented.